1880s basement

[cmoore]

I'm looking for some advice on a basement I am under contract for. The basement is in a high water table area. It is not in a flood zone but outside of one. The seller recently put in two sump pumps and then a plastic vapor barrier down on the dirt floor with stones. When we went to go inspect it, there was standing water on the plastic. IS this normal? What would help remedy this if it already has sump pumps, etc. I am worried that there might be hidden damage in the basement that I cant see..specifically is there a chance that water is eroding the dirt under the foundation. There were no foundation issues that we could see.